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Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.V.Jolos e.A.Kolganova D.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia Dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

In situ Hydrothermal Oxidation of Ternary FeCoNi Alloy electrode for Overall Water Splitting

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energy & environmental Materials 2024年第2期7卷 161-170页

作者： Yuwei Chen Lixia Yang Chao Li Yuqiu Wu Xiao Lν Hairen Wang Jun'e Qu Key Laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China Faculty of Material science and Chemistry China University of GeosciencesWuhan 430074China

exploring noble metal-free catalyst materials for high efficient electrochemical water splitting to produce hydrogen is strongly desired for renewable energy *** this article,a novel bifunctional catalytic electrode of insitu-grown type for alkaline water splitting based on FeCoNi alloy substrate has been successfully prepared via a facile one-step hydrothermal oxidation route in an alkaline hydrogen peroxide *** shows that the matrix alloy with the atom ratio 4∶3∶3 of Fe∶Co∶Ni can obtain the best catalytic performance when hydrothermally treated at 180℃for 18 h in the solution containing 1.8 M hydrogen peroxide and 3.6 M sodium *** as-prepared Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode exhibits small overpotentials of only 184 and 175 mV at electrolysis current density of 10 mA cm^(-2)for alkaline OeR and HeR processes,*** overall water splitting at electrolysis current density of 10 mA cm^(-2)can be stably delivered at a low cell voltage of 1.62 *** characteristics including the large specific surface area,the high surface nickel content,the abundant catalyst species,the balanced distribution between bivalent and trivalent metal ions,and the strong binding of in-situ naturally growed catalytic layer to matrix are responsible for the prominent catalytic performance of the Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode,which can act as a possible replacement for expensive noble metal-based materials.

关键词： alkaline water electrolysis bifunctional electrocatalyst FeCoNi alloy hydrothermal oxidation in-situ growing

First results of turbulence investigation on Globus-M2 using radial correlation Doppler reflectometry

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Plasma Science and Technology 2024年第10期26卷 49-55页

作者： A.PONOMAReNKO A.YASHIN V.GUSeV e.KISeLeV G.KURSKIeV V.MINAeV Y.PeTROV N.SAKHAROV P.SHCHeGOLeV e.TKACHeNKO N.ZHILTSOV Peter the Great St.Petersburg Polytechnic University St.Petersburg 195251Russia Ioffe Institute St.Petersburg 194064Russia

The first results of investigation of the turbulence structure using Doppler backscattering(DBS)on the Globus-M2 tokamak are presented.A one-channel DBS system with a variable probing frequency within the 18–26 GHz range was installed to investigate the edge plasma at normalized minor radiiρ=0.9–*** correlation Doppler reflectometry was used to study the changes in turbulence eddies after the LH *** analysis was applied to the phase derivative of complex in-phase and quadrature(IQ)signals of the DBS diagnostic as it contains information about the poloidal plasma rotation *** L-mode,the radial correlation length L_(r)is estimated to be 3 cm and after transition to H-mode reduces to approximately 2 *** modelling in a linear local approximation using code GeNe indicates that the instability with positive growth rate at the normalized minor radiusρ=0.75 in L-mode and H-mode on Globus-M2 was the ion temperature gradient(ITG)mode.

关键词： tokamak turbulence Doppler backscattering correlation reflectometry

Current considerations on intraductal papillary neoplasms of the bile duct and pancreatic duct

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World Journal of Gastroenterology 2024年第10期30卷 1461-1465页

作者： efstathios T Pavlidis Ioannis N Galanis Theodoros e Pavlidis 2^(nd) Propedeutic Department of Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Pancreatobiliary intraductal papillary neoplasms(IPNs)represent precursors of pancreatic cancer or bile duct cholangiocarcinoma that can be detected and *** advances in diagnostic methods,identifying these premalignant lesions is still challenging for treatment *** imaging,biomarkers and molecular tests for genomic alterations can be used for diagnosis and *** intervention in combination with new chemotherapeutic agents is considered the optimal treatment for malignant *** balance between the risk of malignancy and any risk of resection guides management policy;therefore,treatment should be individualized based on a meticulous preoperative assessment of high-risk *** of the bile duct is more aggressive;thus,early diagnosis and surgery are *** conservative management of low-risk pancreatic branch-duct lesions is safe and effective.

关键词： Biliary tree diseases Pancreatic cystic neoplasms Biliary tract neoplasms extrahepatic cholangiocarcinoma Pancreatic adenocarcinoma

evolution, divergence, and convergence in the mandibles of opossums (Didelphidae, Didelphimorphia)

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Current Zoology 2024年第4期70卷 488-504页

作者： Franciscodas Chagas Silva-Neto Silvia e.Pavan Diego Astua Laboratorio de Mastozoologia Departamento de ZoologiaUniversidade Federal de Pernambuco.Av.Prof.Moraes Regos.n.Cidade Universitaria.50670-901RecifePEBrazil Department of Biological Sciences California State Polytechnic UniversityHumboldt1Harpst StreetArcataCA95521USA

Didelphid marsupials are considered a morphologically unspecialized group with a generalist diet that includes vertebrates,invertebrates,and plant *** cranium and scapula variation has alreadybeen examined within Didelphidae,variation inmandible shape,usually associated with diet or phylogeny in other mammalian groups,has not yet been properly assessed in the *** evaluated the variation in mandible shape and size of didelphids(2470 specimens belonging to 94 species)using 2D geometric *** classified the diet of the didel-phids into four broad categories to assess whether morphospace ordination relates to dietary *** also provided the most comprehensive phylogeny for the family(i23 out of the 126 living species)using 10 nuclear and mitochondrial *** then mapped mandible size and shape onto that phylogeny for 93 selected taxa and ancestral size and shapes were reconstructed by *** found phylogenetically structured variation in mandible morphology between didelphid groups,and our results indicate that they have a significant phylogenetic *** main axis of shape variation is poorly related to size,but the second is strongly allometric,indicating that allometry is not the main factor in shaping morphological diversity on their *** results indicate that the shape and size of the ancestral mandible of didelphids would be similar to that of the current species of the genus Marmosa.

关键词： mandible Didelphimorphia morphological evolution allometry phylogeny diet.

Orbit Weighting Scheme in the Context of Vector Space Information Retrieval

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Computers, Materials & Continua 2024年第7期80卷 1347-1379页

作者： Ahmad Ababneh Yousef Sanjalawe Salam Fraihat Salam Al-e’mari Hamzah Alqudah Department of Computer Science Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan Department of Cybersecurity Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan Artificial Intelligence Research Center(AIRC) College of Engineering and Information TechnologyAjman UniversityP.O.Box 346Ajman13306United Arab Emirates Information Security Department Faculty of Information TechnologyUniversity of PetraAmman11196Jordan Department of Data Science and Artificial Intelligence Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan

This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schemes like tf-idf and *** conventional methods often struggle with accurately capturing document relevance,leading to inefficiencies in both retrieval performance and index size *** proposes a dynamic weighting mechanism that evaluates the significance of terms based on their orbital position within the vector space,emphasizing term relationships and distribution patterns overlooked by existing *** research focuses on evaluating OWS’s impact on model accuracy using Information Retrieval metrics like Recall,Precision,InterpolatedAverage Precision(IAP),andMeanAverage Precision(MAP).Additionally,we assessOWS’s effectiveness in reducing the inverted index size,crucial for model *** compare OWS-based retrieval models against others using different schemes,including tf-idf variations and *** reveal OWS’s superiority,achieving a 54%Recall and 81%MAP,and a notable 38%reduction in the inverted index *** highlights OWS’s potential in optimizing retrieval processes and underscores the need for further research in this underrepresented area to fully leverage OWS’s capabilities in information retrieval methodologies.

关键词： Information retrieval orbit weighting scheme semantic text analysis Tf-Idf weighting scheme vector space model

effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah C.Keles W.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

Investigations of nuclear chirality at iThemba LABS

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Frontiers of physics 2024年第2期19卷 7-38页

作者： R.A.Bark e.A.Lawrie C.Liu S.Y.Wang iThemba Laboratory for Accelerator Based Sciences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of chirality in atomic nuclei at iThemba LABS is *** regions of chirality,around mass 80 and 190 have been discovered using the AFRODITe array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple chiral bands in the same nucleus,the coexistence of octupole correlations and nuclear chirality,and the coexistence of pseudo spin and nuclear *** best example of chiral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of chirality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the calculations showed that nuclear chirality can persist.

关键词： chirality high-spin states particle-rotor model

A holistic approach to improving safety for battery energy storage systems

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Journal of energy Chemistry 2024年第5期92卷 422-439页

作者： James Close Jonathan e.Barnard Y.M.John Chew Semali Perera Department of Chemical engineering Centre for DigitalManufacturing&DesignUniversity of BathBath BA27AYUK ioMosaic International Limited 16-18 Queen SquareBath BA12HNUK

The integration of battery energy storage systems(BeSS)throughout our energy chain poses concerns regarding safety,especially since batteries have high energy density and numerous BeSS failure events have *** spread adoption will only increase the prevalence of these failure events unless there is a step change in the management and design of *** understand the causes of failure,the main challenges of BeSS safety are *** consequences and failure events are discussed,including specific focus on the chain of events causing thermal runaway,and a case study of a BeSS explosion in Surprise Arizona is *** on the technology and past events,a paradigm shift is required to improve BeSS *** this review,a holistic approach is *** combines currently adopted approaches including battery cell testing,lumped cell mathematical modelling,and calorimetry,alongside additional measures taken to ensure BeSS safety including the requirement for computational fluid dynamics and kinetic modelling,assessment of installation level testing of the full BeSS system and not simply a single cell battery test,hazard and layers of protection analysis,gas chromatography,and composition *** holistic approach proposed in this study aims to address challenges of BeSS safety and form the basis of a paradigm shift in the safety management and design of these systems.

关键词： energy storagesystems Process safety Battery safety Thermal safety